Accessory element for window system



FIG. 1 is a perspective view taken from the front, bottom and right side of an accessory element for window system;

FIG. 2 is a perspective view taken from the front, top and right side of the accessory element for window system of FIG. 1; and,

FIG. 3 is a bottom plan view of the accessory element for window system of FIG. 1.

The left side of the accessory element for window system of FIG. 1 is a mirror image of the right side, and the rear of the accessory element for window system of FIG. 1 is a mirror image of the front.

The broken lines of the drawings disclose environmental structure that forms no part of the claimed design. 

CLAIM The ornamental design for an accessory element for window system, as shown and described. 